The present invention relates to a disk brake caliper mounting bracket for mounting to a rear end of an automobile, and especially to an automobile adapted for stock car or circle track type racing.
These types of racing vehicles often use rear ends that are assembled from a number of separate components. For instance, FIG. 1 (Prior Art) shows an axle tube 100 adapted to mount on opposite sides to a center differential. As is known, these axle tubes provide a housing in which the respective axles rotate to transmit power from the differential to the driving wheels. The axle tubes 100 can be constructed of steel, aluminum, or other material. Wheel mounts 102, such as shown in FIG. 2 (Prior Art) mount to outboard ends of the axle tubes 100 with a plurality of bolts to rotationally support a wheel, as is known. See FIG. 3 (Prior Art). The wheel mount has an axle tube end 132 sized and adapted to engage an internal bore 134 of the axle tube 100. In one embodiment, the axle tube 100 has a thickened wall section 120 to accommodate a plurality of axially oriented threaded bores 122 circumferentially spaced around the axle tube 100. In a common known configuration, there are eight threaded bores 122 equally spaced around the thickened wall section 120. Eight alien head bolts are positioned through eight correspondingly positioned through-bores 136 on a circular flange portion 138 of the wheel mount 102 to engage the respective threaded bores 122 and attach the wheel mount 102 to the axle tube 100. The number of bores and bolts used to attach the wheel mount 102 to the axle tube 100 can be altered as desired.
Each wheel mount 102 is typically machined (from steel) so that once mounted to the respective axle tube 100, the wheel mount 102 will provide a camber to the wheel once the wheel is mounted on the wheel mount 102. In other words, a first portion 104 of the wheel mount 102 will be aligned with an axis of the axle tube 100 while a second portion 106 of the wheel mount which supports the wheel will be machined to be at an angle to the axle tube 100. This angle, the camber, is typically selected to be between 0 and 2.5°, often in discrete 0.5° steps, but can be lesser or greater. The camber is shown as angle θ in FIG. 3 (Prior Art), with the left leg of the angle being perpendicular to an axis 124 of the axle tube 100 and the right leg of the angle being perpendicular to an axis 126 of a wheel mounting portion 128 of the wheel mount 102. In other words, the camber is the acute angle formed between the intersection of the axis 124 and the axis 126. If it is desired to alter the camber for a desired chassis set-up, the wheel mount 102 is removed from the end of the axle tube 100 and a different wheel mount 102 having the desired camber is reinstalled in the axle tube 100. Known wheel mounts 102 are generally offered in 0.5° increments from 0 to 2.5° camber. As best seen in FIGS. 2 and 3, an outboard end 108 of the wheel mount 102 is threaded to accept a single retaining nut.
Other structure can be attached to the exterior of the axle tubes 100 for mounting other components to the rear end, such as for instance, shock absorbers, tracking bars and brake mounting brackets. Various configurations of disk brake caliper mounting brackets 110 are known that clamp to an exterior circumference of the axles tubes 100 for mounting disk brake calipers to the rear end. These disk brake calipers work in a known manner with disk brake rotors mounted to the wheels to brake the vehicle. In known alternative embodiments, the caliper mounting brackets 112 are welded on the exterior of the axle tubes 100. In either of these embodiments, it is extremely important to accurately align the caliper mounting brackets with respect to the axle tubes 100 before fixedly attaching the brackets to the axle tubes. The caliper mounting brackets must be both positioned at a correct axial distance from the wheel mount to properly center the mounted brake caliper over the brake rotor, and be aligned at the proper angle such that the brake caliper is mounted parallel with the brake rotor. The caliper mounting bracket must also mount the brake caliper at a proper radial distance from the axle tube so that the brake caliper is mounted at a desired radial position with respect to the brake rotor. Otherwise, the calipers, once mounted to the mounting brackets, will not be in proper position and alignment with respect to the brake rotors and braking performance will suffer.
It has been found that with the conventional caliper mounting brackets, correctly positioning and aligning the caliper mounting brackets on the axle tubes is a difficult and time-consuming process. Even when the process is performed carefully, it is still extremely difficult to get an exact positioning and alignment of the caliper mounting brackets. This can result in having to shim the brake calipers on the caliper mounting brackets to get the desired positioning and alignment of the brake calipers. This shimming process is also time-consuming and is not preferred. Furthermore, if it is desired to change the camber of the axle stubs for a different chassis set-up, it will be necessary to reposition and/or realign the caliper mounting brackets to maintain the desired positioning and alignment of the brake calipers with respect to the brake rotors. This process is complicated by the fact that the known caliper mounting brackets tend to come in only a single version with a fixed alignment angle to accommodate for the camber of the axle stub. This fixed alignment angle is thus, by definition, not parallel with the brake rotor if the camber of the axle stub is then changed. At the very least, changing the camber of the axle stubs can entail repositioning and realigning the clamp-on style caliper mounting brackets. The weld-on style caliper mounting brackets, being welded to the axle tubes, cannot be repositioned easily. In either case, shimming is still likely to be required between the caliper mounting brackets and the brake calipers to get a desired positioning and alignment of the brake calipers with respect to the brake rotors, especially if the camber of the axle stub is not the same as the fixed alignment angle of the caliper mounting bracket.
It is desired to provide a caliper mounting bracket that overcomes the above deficiencies of the known caliper mounting brackets and which is simple and quick to install while achieving a desired positioning and alignment of the brake caliper.